U.S. patent application Ser. No. 802,347, filed Nov. 27, 1985, entitled "Molded Case Circuit Breaker Modular Support", filed concurrently with the instant application, describes a modular plastic saddle that is robotically assembled. The modular sections of the saddle allow for the manufacture of load centers and panel boards having any number of circuit breakers attached. The saddles serve to support the main busses and branch straps as well as the neutral terminal conductors for connection with the circuit breakers. To electrically insulate between the branch straps and main busbars, a plurality of electrically insulating phase barriers are arranged on the surface of the saddle, and in some molded plastic saddle designs, are integrally formed therein. With the introduction of the aforementioned modular plastic saddle wherein any number of circuit breakers are robotically assembled to the saddle with a minimum number of inventoried parts, it is more economically feasible to provide modularity with respect to the phase barriers utilized with the precise number of circuit breakers. This is accomplished by the phase barriers of the instant invention which are fabricated from a single thermoplastic part that is interchangeable over a wide range of load center and panel board designs and which can be arranged in accordance with the exact number of circuit breakers on each saddle.